Turbine component with heated structure to reduce thermal stress

TECHNICAL FIELD

0001The disclosure relates generally to turbomachines and, more particularly, to a turbine component including fluid passages in a structure thereof configured to increase a temperature of the structure and reduce temperature differences that result in thermal stress.

BACKGROUND

0002Temperature differences between parts of a turbine component can cause thermal stress in the component. The thermal stress can cause earlier than expected maintenance and/or shorten the useful life of the component. Turbine components are cooled to prevent damage from a hot gas path of the turbine, but conventional cooling schemes do not mitigate the thermal stress experienced by components of the turbomachine caused by temperature differences.

BRIEF DESCRIPTION

0003All aspects, examples, and features mentioned below can be combined in any technically possible way.

0004An aspect of the disclosure includes a turbine component having a first structure exposed to a hot gas path and a second structure integral with the first structure but isolated from the hot gas path. A first fluid passage in the first structure delivers a thermal transfer fluid, e.g., a coolant such as air, through at least a portion of the first structure to cool the first structure. A second fluid passage is defined within at least a portion of the second structure and is in fluid communication with the first fluid passage. After heat transfer in the first structure, the thermal transfer fluid is hotter than a temperature of the second structure and thus increases the temperature of the second structure. The heat transfer to the second structure reduces a temperature difference between the first structure and the second structure that would, without heating, cause thermal stress between the structures. The heating of the second structure reduces the need for early maintenance and lengthens the lifespan of the component.

0005An aspect of the disclosure provides a turbine component, comprising: a first structure integrally coupled to a second structure; a first fluid passage defined in the first structure for delivering a first thermal transfer fluid through at least a portion of the first structure; and a second fluid passage defined within at least a portion of the second structure, the second fluid passage in fluid communication with the first fluid passage downstream of the first structure, wherein the first structure includes at least one surface thereof directly exposed to a hot gas path of a turbine, and the second structure is not directly exposed to the hot gas path of the turbine, and wherein a temperature of the first thermal transfer fluid entering the first structure in the first fluid passage is less than a temperature of the first structure to reduce the temperature of the first structure, and the temperature of the first thermal transfer fluid entering the second structure in the second fluid passage is greater than a temperature of the second structure to increase the temperature of the second structure.

0006Another aspect of the disclosure includes any of the preceding aspects, and the first structure includes at least one of an airfoil, a platform coupled to the airfoil and a slash face of the platform, and wherein the second structure includes a radially extending mounting rail coupled to the platform.

0007Another aspect of the disclosure includes any of the preceding aspects, and further comprising a third structure integrally coupled to the second structure and a third fluid passage defined within at least a portion of the third structure, wherein the third fluid passage is in fluid communication with the second fluid passage downstream of the second structure, and wherein the first thermal transfer fluid is used to at least one of: cool the third structure and function as a purge gas exiting the third structure.

0008Another aspect of the disclosure includes any of the preceding aspects, and the first structure includes at least one of an airfoil, a platform coupled to the airfoil and a slash face of the platform, wherein the second structure includes at least part of a radially extending mounting rail coupled to the platform, and wherein the third structure includes at least one of a slash face of the platform, an exterior surface of the airfoil and a trailing edge of the airfoil.

0009Another aspect of the disclosure includes any of the preceding aspects, and the second fluid passage has a non-linear path through the second structure.

0010Another aspect of the disclosure includes any of the preceding aspects, and the second fluid passage includes a plurality of fluid passages fluidly coupled by an upstream manifold at an upstream end thereof and fluidly coupled by a downstream manifold at a downstream end thereof.

0011Another aspect of the disclosure includes any of the preceding aspects, and further comprising a third structure integrally coupled to the second structure and in closer proximity to the hot gas path than the second structure; a third fluid passage defined in the third structure for delivering a second thermal transfer fluid through at least a portion of the third structure; and a fourth fluid passage defined within at least a portion of the second structure, the fourth fluid passage in fluid communication with the third fluid passage downstream of the third structure, wherein a temperature of the second thermal transfer fluid entering the third structure in the third fluid passage is less than a temperature of the third structure to reduce the temperature of the third structure, and the temperature of the second thermal transfer fluid entering the second structure in the fourth fluid passage is greater than a temperature of the second structure to increase the temperature of the second structure.

0012Another aspect of the disclosure includes any of the preceding aspects, and the first thermal transfer fluid in the second fluid passage in the second structure flows in a first direction in the second structure compared to a second, opposite direction of flow of the second thermal transfer fluid in the fourth fluid passage in the second structure.

0013An aspect of the disclosure also includes a turbine nozzle, comprising: an airfoil; a platform coupled to the airfoil, the platform including a radially extending mounting rail; a first fluid passage defined in at least one of the airfoil and the platform for delivering a first thermal transfer fluid therethrough; and a second fluid passage extending within at least a portion of a circumferential length of the radially extending mounting rail, the second fluid passage in fluid communication with the first fluid passage.

0014Another aspect of the disclosure includes any of the preceding aspects, and the airfoil and at least one surface of the platform are directly exposed to a hot gas path of a turbine, and the radially extending mounting rail is not directly exposed to the hot gas path of the turbine, and wherein a temperature of the first thermal transfer fluid entering the first fluid passage in the one of the airfoil and the platform is less than a temperature of the one of the airfoil and the platform to reduce the temperature of the one of the airfoil and the platform, and the temperature of the first thermal transfer fluid entering the second fluid passage in the radially extending mounting rail is greater than a temperature of the radially extending mounting rail to increase the temperature of the radially extending mounting rail.

0015Another aspect of the disclosure includes any of the preceding aspects, and further comprising an additional structure integrally coupled to the radially extending mounting rail and in closer proximity to the hot gas path than the radially extending mounting rail; and a third fluid passage defined within at least a portion of the additional structure, wherein the third fluid passage is in fluid communication with the second fluid passage downstream of the radially extending mounting rail, wherein the first thermal transfer fluid is used to at least one of: cool the additional structure and function as a purge gas exiting the additional structure.

0016Another aspect of the disclosure includes any of the preceding aspects, and the additional structure includes at least one of a slash face of the platform, an exterior surface of the airfoil, and a trailing edge of the airfoil.

0017Another aspect of the disclosure includes any of the preceding aspects, and further comprising: a fourth fluid passage defined in the additional structure for delivering a second thermal transfer fluid through at least a portion of the additional structure; and a fifth fluid passage defined within at least a portion of the radially extending mounting rail, the fifth fluid passage in fluid communication with the fourth fluid passage downstream of the additional structure, wherein a temperature of the second thermal transfer fluid entering the additional structure in the fourth fluid passage is less than a temperature of the additional structure to reduce the temperature of the additional structure, and the temperature of the second thermal transfer fluid entering the radially extending mounting rail in the fifth fluid passage is greater than a temperature of the radially extending mounting rail to increase the temperature of the radially extending mounting rail, and wherein the first thermal transfer fluid in the second fluid passage in the radially extending mounting rail flows in a first direction in the radially extending mounting rail compared to a second, opposite direction of flow of the second thermal transfer fluid in the fifth fluid passage in the radially extending mounting rail.

0018Another aspect of the disclosure includes any of the preceding aspects, and the second fluid passage has a non-linear path through the radially extending mounting rail.

0019Another aspect of the disclosure includes any of the preceding aspects, and the second fluid passage includes a plurality of fluid passages fluidly coupled by an upstream manifold at an upstream end thereof and fluidly coupled by a downstream manifold at a downstream end thereof.

0020An aspect of the disclosure relates to a method of reducing thermal stress in a turbine component of a turbine, the method comprising: in a turbine component of a turbine: decreasing a temperature of a first structure of the turbine component by passing a first thermal transfer fluid having a temperature lower than the first structure through a first fluid passage defined in the first structure; and increasing a temperature of a second structure of the turbine component that is integrally coupled to the first structure by passing the first thermal transfer fluid through a second fluid passage defined in the second structure after passing the first thermal transfer fluid through the first fluid passage in the first structure, wherein at least part of the first structure is directly exposed to a hot gas path (HGP) of the turbine, and the second structure is not exposed to the HGP of the turbine.

0021Another aspect of the disclosure includes any of the preceding aspects, and further comprising passing the first thermal transfer fluid through a third structure of the turbine component that is integrally coupled to the second structure after passing the first thermal transfer fluid through the second fluid passage in the second structure, wherein the first thermal transfer fluid is passed through a third fluid passage defined in the third structure to at least one of: cool the third structure and be discharged to an area exterior of the third structure as a purge gas.

0022Two or more aspects described in this disclosure, including those described in this summary section, may be combined to form implementations not specifically described herein.

0023The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects and advantages will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

0024These and other features of this disclosure will be more readily understood from the following detailed description of the various aspects of the disclosure taken in conjunction with the accompanying drawings that depict various embodiments of the disclosure, in which:

0025<figref idref="DRAWINGS">FIG. <b>1</b></figref> shows a schematic view of an illustrative turbomachine in the form of a gas turbine system;

0026<figref idref="DRAWINGS">FIG. <b>2</b></figref> shows a cross-sectional view of an illustrative gas turbine assembly that may be used with the gas turbine system in <figref idref="DRAWINGS">FIG. <b>1</b></figref>;

0027<figref idref="DRAWINGS">FIG. <b>3</b></figref> shows a perspective view of a turbine component in the form of a nozzle, according to embodiments of the disclosure;

0028<figref idref="DRAWINGS">FIG. <b>4</b></figref> shows a perspective view of a turbine component in the form of a shroud, according to embodiments of the disclosure;

0029<figref idref="DRAWINGS">FIG. <b>5</b></figref> shows a partially transparent perspective view of an illustrative turbine component in the form of a nozzle including a heating fluid passage, according to embodiments of the disclosure;

0030<figref idref="DRAWINGS">FIG. <b>6</b></figref> shows a partially transparent perspective view of a turbine component in the form of a nozzle including a heating fluid passage, according to other embodiments of the disclosure;

0031<figref idref="DRAWINGS">FIG. <b>7</b></figref> shows a partially transparent perspective view of a turbine component in the form of a nozzle including a heating fluid passage, according to embodiments of the disclosure;

0032<figref idref="DRAWINGS">FIG. <b>8</b></figref> shows a partially transparent perspective view of a turbine component in the form of a nozzle including a heating fluid passage, according to other embodiments of the disclosure;

0033<figref idref="DRAWINGS">FIG. <b>9</b></figref> shows a partially transparent perspective view of a turbine component in the form of a nozzle including two different heating fluid passages, according to additional embodiments of the disclosure;

0034<figref idref="DRAWINGS">FIG. <b>10</b></figref> shows an enlarged, partially transparent perspective view of a corner of a turbine component in the form of a nozzle including two different heating fluid passages, according to additional embodiments of the disclosure;

0035<figref idref="DRAWINGS">FIG. <b>11</b></figref> shows an enlarged, partially transparent perspective view of a corner of a turbine component in the form of a nozzle including two different heating fluid passages, according to additional embodiments of the disclosure;

0036<figref idref="DRAWINGS">FIG. <b>12</b></figref> shows a schematic perspective view of a heating fluid passage including heat transfer enhancements, according to other embodiments of the disclosure; and

0037<figref idref="DRAWINGS">FIG. <b>13</b></figref> shows a flow diagram of a method of reducing thermal stress in a turbine component of a turbine, according to embodiments of the disclosure.

0038It is noted that the drawings of the disclosure are not necessarily to scale. The drawings are intended to depict only typical aspects of the disclosure and therefore should not be considered as limiting the scope of the disclosure. In the drawings, like numbering represents like elements between the drawings.

DETAILED DESCRIPTION

0039As an initial matter, in order to clearly describe the subject matter of the current disclosure, it will become necessary to select certain terminology when referring to and describing relevant machine components within a turbomachine. To the extent possible, common industry terminology will be used and employed in a manner consistent with its accepted meaning. Unless otherwise stated, such terminology should be given a broad interpretation consistent with the context of the present application and the scope of the appended claims. Those of ordinary skill in the art will appreciate that often a particular component may be referred to using several different or overlapping terms. What may be described herein as being a single part may include and be referenced in another context as consisting of multiple components. Alternatively, what may be described herein as including multiple components may be referred to elsewhere as a single part.

0040In addition, several descriptive terms may be used regularly herein, and it should prove helpful to define these terms at the onset of this section. These terms and their definitions, unless stated otherwise, are as follows. As used herein, “downstream” and “upstream” are terms that indicate a direction relative to the flow of a fluid, such as the coolant through components of the turbine engine. The term “downstream” corresponds to the direction of flow of the fluid, and the term “upstream” refers to the direction opposite to the flow (i.e., the direction from which the flow originates). The terms “forward” and “aft,” without any further specificity, refer to directions, with “forward” referring to the front or compressor end of the engine, and “aft” referring to the rearward section of the turbomachine.

0041It is often required to describe parts that are disposed at different radial positions with regard to a center axis. The term “radial” refers to movement or position perpendicular to an axis. For example, if a first component resides closer to the axis than a second component, it will be stated herein that the first component is “radially inward” or “inboard” of the second component. If, on the other hand, the first component resides further from the axis than the second component, it may be stated herein that the first component is “radially outward” or “outboard” of the second component. The term “axial” refers to movement or position parallel to an axis. Finally, the term “circumferential” refers to movement or position around an axis. It will be appreciated that such terms may be applied in relation to the center axis of the turbine or to a centerline axis of a component, such as a turbine nozzle.

0042In addition, several descriptive terms may be used regularly herein, as described below. The terms “first,” “second,” and “third,” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components.

0043The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms “a,” an, and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur or that the subsequently described component or element may or may not be present, and that the description includes instances where the event occurs or the component is present and instances where it does not or is not present.

0044Where an element or layer is referred to as being “on,” “engaged to,” “connected to” or “coupled to” another element or layer, it may be directly on, engaged to, connected to, or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to” or “directly coupled to” another element or layer, no intervening elements or layers are present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

0045As indicated above, the disclosure provides a turbine component including a first structure or part integrally coupled to a second structure or part thereof. A first fluid passage is defined in the first structure for delivering a first thermal transfer fluid, e.g., a coolant such as air, through at least a portion of the first structure. A second fluid passage is defined within at least a portion of the second structure. The second fluid passage is in fluid communication with the first fluid passage downstream of the first structure. A temperature of the first thermal transfer fluid entering the first structure in the first fluid passage is less than a temperature of the first structure to reduce the temperature of the first structure. After heat transfer in the first structure, the heat transfer fluid is hotter such that the temperature of the first thermal transfer fluid entering the second structure in the second fluid passage is greater than a temperature of the second structure to increase the temperature of the second structure.

0046The heat transfer to the second structure reduces a temperature difference between the second structure and the first structure that would, without heating, cause thermal stress between the structures. In certain embodiments, the turbine component includes a nozzle, the first structure includes a platform of the nozzle, and the second structure includes a mounting rail of the nozzle. The thermal stress can cause bowing of the mounting rail, but with heating of the mounting rail as provided herein, the bowing is eliminated or greatly reduced. The heating of the mounting rail reduces temperature differences and thermal stress, reducing the need for maintenance and lengthening the lifespan of the component.

0047<figref idref="DRAWINGS">FIG. <b>1</b></figref> shows a schematic view of an illustrative turbomachine <b>100</b>. Some of the turbine components of turbomachine <b>100</b> may include fluid passages according to teachings of the disclosure. In the example, turbomachine <b>100</b> is in the form of a combustion or gas turbine system. Turbomachine <b>100</b> includes a compressor <b>102</b> and a combustor <b>104</b>. Combustor <b>104</b> includes a combustion region <b>106</b> and a fuel nozzle assembly <b>108</b>. Turbomachine <b>100</b> also includes a turbine assembly <b>110</b> and a common compressor/turbine shaft <b>112</b> (hereinafter referred to as a rotor <b>112</b>).

0048In one embodiment, turbomachine <b>100</b> may be any HA or F model gas turbine (GT) system, commercially available from General Electric Company, Greenville, S.C. The present disclosure is not limited to any one particular GT system and may be implemented in connection with other engines including, for example, the other B, LM, GT, TM and E-class engine models of General Electric Company, and engine models of other companies. The present disclosure is not limited to any particular turbine or turbomachine, and may be applicable to, for example, steam turbines, jet engines, compressors, turbofans, etc. Furthermore, the present disclosure is not limited to any particular component and may be applied to any form of turbine component requiring reduction of thermal stress caused by temperature differences within structures of the component.

0049Continuing with <figref idref="DRAWINGS">FIG. <b>1</b></figref>, air flows through compressor <b>102</b> and compressed air is supplied to combustor <b>104</b>. Specifically, the compressed air is supplied to fuel nozzle assembly <b>108</b> that is integral to combustor <b>104</b>. Fuel nozzle assembly <b>108</b> is in flow communication with a fuel source and channels fuel and air to combustion region <b>106</b>. Combustor <b>104</b> ignites and combusts fuel.

0050Combustor <b>104</b> is in flow communication with turbine assembly <b>110</b> within which gas stream thermal energy is converted to mechanical rotational energy. Turbine assembly <b>110</b> includes a turbine <b>111</b> that rotatably couples to and drives rotor <b>112</b>. Compressor <b>102</b> also is rotatably coupled to rotor <b>112</b>. In the illustrative embodiment, there are a plurality of combustors in combustion region <b>106</b> (e.g., within a circumferential array) and a plurality of fuel nozzle assemblies <b>108</b>.

0051<figref idref="DRAWINGS">FIG. <b>2</b></figref> shows a cross-sectional view of a part of an illustrative turbine assembly <b>110</b> of turbomachine <b>100</b> (<figref idref="DRAWINGS">FIG. <b>1</b></figref>). Turbine <b>111</b> of turbine assembly <b>110</b> includes a row or stage of nozzles <b>120</b> coupled to a stationary casing <b>122</b> of turbomachine <b>100</b> and axially adjacent a row or stage of rotating blades <b>124</b>. A stationary nozzle <b>126</b> (also known as a vane) may be held in turbine assembly <b>110</b> by a radially outer platform <b>128</b> and a radially inner platform <b>130</b>. Platforms <b>128</b>, <b>130</b> may also be referred to as endwalls. As will be described herein, radially outer platform <b>128</b> includes a radially extending mounting rail <b>232</b> (<figref idref="DRAWINGS">FIG. <b>5</b></figref>). Each stage of blades <b>124</b> in turbine assembly <b>110</b> includes rotating blades <b>132</b> coupled to rotor <b>112</b> and rotating with the rotor. Rotating blades <b>132</b> may include a radially inner platform <b>134</b> (at a root of the blade) coupled to rotor <b>112</b> and a radially outer tip <b>136</b> (at a tip of the blade). Shrouds <b>138</b> may separate adjacent stages of nozzles <b>126</b> and rotating blades <b>132</b>.

0052A working fluid <b>140</b>, including for example combustion gases in the example gas turbine, passes through turbine <b>111</b> along what is referred to as a hot gas path (hereafter “HGP”). The HGP can be any area of turbine <b>111</b> exposed to combustion gases having hot temperatures. Various components of turbine <b>111</b> are exposed directly or indirectly to the HGP and may comprise a “turbine component.” In the example turbine <b>111</b>, nozzles <b>126</b> and shrouds <b>138</b> are all examples of turbine components that may benefit from the teachings of the disclosure. It will be recognized that other parts of turbine <b>111</b> exposed directly or indirectly to the HGP may also be considered turbine components capable of benefiting from the teachings of the disclosure.

0053<figref idref="DRAWINGS">FIGS. <b>3</b>-<b>4</b></figref> show perspective views of examples a turbine component <b>200</b> in which teachings of the disclosure may be employed.

0054<figref idref="DRAWINGS">FIG. <b>3</b></figref> shows a perspective view of a turbine component <b>200</b> in the form of a stationary nozzle <b>126</b>. Nozzle <b>126</b> includes radial outer platform <b>128</b> by which nozzle <b>126</b> attaches to stationary casing <b>122</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>) of the turbomachine. Outer platform <b>128</b> may include any now known or later developed mounting configuration for mounting in a corresponding mount in casing <b>122</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>). Nozzle <b>126</b> may further include radially inner platform <b>130</b> for positioning between platforms <b>134</b> of adjacent turbine rotating blades <b>132</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>). Platforms <b>128</b>, <b>130</b> define respective portions of the outboard and inboard boundary of the HGP through turbine assembly <b>110</b>, and hence are directly exposed to the HGP.

0055It will be appreciated that airfoil <b>176</b> is the active component of nozzle <b>126</b> that intercepts the flow of working fluid and directs it towards turbine rotating blades <b>132</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>). Airfoil <b>176</b> is thus also directly exposed to the HGP. It will be seen that airfoil <b>176</b> of nozzle <b>126</b> includes a concave pressure side (PS) outer wall <b>178</b> and a circumferentially or laterally opposite convex suction side (SS) outer wall <b>180</b> extending axially between opposite leading and trailing edges <b>182</b>, <b>184</b>, respectively. Walls <b>178</b> and <b>180</b> also extend in the radial direction from platform <b>130</b> to platform <b>128</b>. Fluid passages according to embodiments of the disclosure can be used, for example, within platforms <b>128</b>, <b>130</b> or other parts of nozzle <b>126</b>. With respect to nozzle <b>126</b>, the circumferential direction is indicated by the arrow labeled “C”, the axial direction by the arrow labeled “X”, and the radial direction by the arrow labeled “Z”, where such directions are relative to a gas turbine centerline (i.e., through rotor <b>112</b>).

0056<figref idref="DRAWINGS">FIG. <b>4</b></figref> shows a perspective view of turbine component <b>200</b> in the form of a shroud <b>138</b>. Shroud <b>138</b> may include a platform <b>190</b> for positioning between tips <b>136</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>) of turbine rotating blades <b>132</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>) and radially outer platforms <b>128</b> (<figref idref="DRAWINGS">FIGS. <b>2</b>-<b>3</b></figref>) of nozzles <b>126</b> (<figref idref="DRAWINGS">FIGS. <b>2</b>-<b>3</b></figref>). Shroud <b>138</b> may be fastened to casing <b>122</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>) in any fashion. Fluid passages according to embodiments of the disclosure can be used, for example, within a mounting rail <b>192</b> or other parts of shroud <b>138</b>. With respect to shroud <b>138</b>, the circumferential direction is indicated by the arrow labeled “C”, the axial direction by the arrow labeled “X”, and the radial direction by the arrow labeled “Z”, where such directions are relative to a gas turbine centerline (i.e., through rotor <b>112</b>).

0057Referring collectively to <figref idref="DRAWINGS">FIGS. <b>3</b>-<b>4</b></figref>, as noted, embodiments of the disclosure described herein may be applied to any turbine component <b>200</b> of turbine <b>111</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>), such as but not limited to nozzles <b>126</b> (<figref idref="DRAWINGS">FIG. <b>3</b></figref>) and/or shrouds <b>138</b> (<figref idref="DRAWINGS">FIG. <b>4</b></figref>). It will be recognized that the turbine components <b>200</b> oftentimes include one or more structures having fluid passages (oftentimes as part of larger cooling circuits) to deliver a coolant to structures or parts thereof exposed to the HGP of turbine <b>111</b> to cool those parts. In contrast to conventional cooling circuits, embodiments of the disclosure implement a fluid passage(s), e.g., passage <b>230</b> (<figref idref="DRAWINGS">FIG. <b>5</b></figref>), that heats a structure or part of turbine component <b>200</b> to reduce a temperature difference between structures and to reduce thermal stress in turbine component <b>200</b>.

0058Referring to <figref idref="DRAWINGS">FIGS. <b>5</b>-<b>9</b></figref>, for purposes of description, the fluid passages according to embodiments of the disclosure will be illustrated and described relative to nozzle <b>126</b> and, more particularly, a radially outer platform <b>128</b> of nozzle <b>126</b>. In certain embodiments, nozzle <b>126</b> may be a first stage nozzle, i.e., the left-most stage in <figref idref="DRAWINGS">FIG. <b>2</b></figref>, but it could be located at any stage. It is emphasized that the teachings of the disclosure may be applied to any turbine component <b>200</b> having two integral structures that observe different temperatures that cause thermal stress.

0059<figref idref="DRAWINGS">FIG. <b>5</b></figref> shows a partially transparent perspective view of turbine component <b>200</b> in the form of nozzle <b>126</b> including a heating fluid passage <b>230</b>, according to embodiments of the disclosure. As shown in <figref idref="DRAWINGS">FIG. <b>5</b></figref>, turbine component <b>200</b> in the form of nozzle <b>126</b> includes a first structure or part <b>210</b> integrally coupled to a second structure or part <b>212</b>. First structure <b>210</b> may include at least one surface <b>214</b> directly exposed to the HGP of turbine <b>111</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>), or in any event, exposed to a heat source in a manner that has a hotter temperature and/or requires cooling of the structure. In the nozzle <b>126</b> example, first structure <b>210</b> may include at least one of airfoil <b>176</b>, platform <b>128</b> coupled to airfoil <b>176</b> and a slash face <b>216</b> of platform <b>128</b>. A slash face <b>216</b> is a surface of platform <b>128</b> that faces a similar surface of an adjacent nozzle <b>126</b>.

0060In the nozzle <b>126</b> example, second structure <b>212</b> may include a radially extending mounting rail <b>232</b> that is integral with platform <b>128</b>. Radially extending mounting rail <b>232</b> (hereinafter “mounting rail <b>232</b>”) may include any now known or later developed structure to couple nozzle <b>126</b> to casing <b>122</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>). Mounting rail <b>232</b> may also be referred to as a hook because of its hook or L-shaped cross-section. Second structure <b>212</b> is not directly exposed to the HGP of turbine <b>111</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>) or, in any event, is not reliant on cooling for operation. Hence, second structure <b>212</b> is cooler in temperature than, for example, first structure <b>210</b>. The temperature difference between first and second structures <b>210</b>, <b>212</b> of turbine component <b>200</b> can create thermal stress between the structures. In some situations, mounting rail <b>232</b> may bow radially outward, creating stress in platform <b>128</b>, for example, where it meets a radially outer end of airfoil <b>176</b> at leading and/or trailing edge <b>182</b>, <b>184</b> (<figref idref="DRAWINGS">FIG. <b>3</b></figref>) of the airfoil. Temperature differences between structures <b>210</b>, <b>212</b> in other turbine components <b>200</b> can create similar thermal stress.

0061A first (cooling) fluid passage <b>220</b> is defined in first structure <b>210</b> for delivering a first thermal transfer fluid <b>222</b> through at least a portion of first structure <b>210</b>. “Thermal transfer fluid” may include any form of fluid capable of heat transfer, such as air from compressor <b>102</b> (<figref idref="DRAWINGS">FIG. <b>1</b></figref>) or another source. As recognized, first thermal transfer fluid <b>222</b> may enter first structure <b>210</b> in any number of locations. Further, first thermal transfer fluid <b>222</b> may pass through portion(s) of first structure <b>210</b> to cool those portion(s) in a large variety of ways. For example, first thermal transfer fluid <b>222</b> may pass through portions of airfoil <b>176</b> in cooling passages or through impingement sleeves, and/or pass through portions of platform <b>128</b> or slash faces <b>216</b> in cooling passages defined therein. In the nozzle <b>126</b> example in <figref idref="DRAWINGS">FIG. <b>5</b></figref>, first fluid passage <b>220</b> may be in at least one of airfoil <b>176</b> and platform <b>128</b> for delivering first thermal transfer fluid <b>222</b> therethrough. For purposes of description, first fluid passage <b>220</b> is shown mainly within platform <b>128</b>, but it could be in any portion of nozzle <b>126</b> that has a hotter temperature and/or that requires cooling. In any event, a temperature of first thermal transfer fluid <b>222</b> entering first structure <b>210</b> in first fluid passage <b>220</b> is less than a temperature of first structure <b>210</b>. Hence, first thermal transfer fluid <b>222</b> in first structure <b>210</b> reduces the temperature of first structure <b>210</b>. While one first fluid passage <b>220</b> is illustrated, any number of first fluid passages <b>220</b> may be present and feed to second fluid passage(s) <b>230</b>.

0062Turbine component <b>200</b> also includes a second (heating) fluid passage <b>230</b> defined within at least a portion of second structure <b>212</b>. Second fluid passage <b>230</b> is in fluid communication with first fluid passage <b>220</b> downstream of first structure <b>210</b> so that first thermal transfer fluid <b>222</b> flows into second fluid passage <b>230</b>. In the nozzle <b>126</b> example, second fluid passage <b>230</b> extends within at least a portion of a circumferential length (see arrow CL) of radially extending mounting rail <b>232</b>. That is, it extends within at least part of radially extending mounting rail <b>232</b> coupled to platform <b>128</b>. In second structure <b>212</b>, first thermal transfer fluid (now labeled <b>240</b>) includes the same form of fluid as in first structure <b>210</b>, e.g., such as air from compressor <b>102</b> (<figref idref="DRAWINGS">FIG. <b>1</b></figref>) or another source, but has a temperature greater than first thermal transfer fluid <b>222</b> when it initially entered first structure <b>210</b>. That is, first thermal transfer fluid <b>240</b> has picked up heat from first structure <b>210</b> via conduction, so that it is hotter than first thermal transfer fluid <b>222</b> that initially enters first structure <b>210</b>. In this manner, a temperature of first thermal transfer fluid <b>240</b> entering second structure <b>212</b> in second fluid passage <b>230</b> is greater than a temperature of second structure <b>212</b> to increase the temperature of second structure <b>212</b>. The increasing of the temperature of second structure <b>212</b> reduces the temperature difference between structures <b>210</b>, <b>212</b>, and reduces the thermal stress between them. In one non-limiting example, first thermal transfer fluid <b>240</b> in second structure <b>212</b> may be 90-150° C. hotter than first thermal transfer fluid <b>222</b> in first structure <b>210</b>.

0063Turbine component <b>200</b> may also include a third structure <b>250</b> integrally coupled to second structure <b>212</b> and a third fluid passage <b>252</b> defined within at least a portion of third structure <b>250</b>. Third fluid passage <b>252</b> is in fluid communication with second fluid passage <b>230</b> downstream of second structure <b>212</b>. In the nozzle <b>126</b> example, third structure <b>250</b> may include a slash face <b>216</b> (nearest viewer in <figref idref="DRAWINGS">FIG. <b>5</b></figref>) of platform <b>128</b>, but it could include a wide variety of parts of nozzle <b>126</b> requiring cooling by thermal transfer fluid and/or requiring purge using the thermal transfer fluid to reduce gas ingestion between parts. For example, third structure <b>250</b> may include at least one of slash face <b>216</b> of platform <b>128</b>, an exterior surface of airfoil <b>176</b>, and/or trailing edge <b>184</b> (<figref idref="DRAWINGS">FIG. <b>3</b></figref>) of airfoil <b>176</b>. Third structure <b>250</b> is disposed in closer proximity to the hot gas path than second structure <b>212</b>.

0064In third structure <b>250</b>, first thermal transfer fluid (now labeled <b>254</b>) includes the same form of fluid as in first and second structures <b>210</b>, <b>212</b>, e.g., such as air from compressor <b>102</b> (<figref idref="DRAWINGS">FIG. <b>1</b></figref>) or another source, but has a temperature lower than first thermal transfer fluid <b>240</b> when it initially entered second structure <b>212</b>. First thermal transfer fluid <b>254</b> in third structure <b>250</b> may be used, for example, to cool third structure <b>250</b> (after its temperature is reduced within second structure <b>212</b>) and/or as purge gas out of third structure <b>250</b> to prevent ingestion of gases into turbine component <b>200</b>. When used for cooling, first thermal transfer fluid <b>254</b> may pass to any other downstream structure for additional cooling or other use, e.g., additional cooling or purge gas. When used for purge gas, first thermal transfer fluid <b>254</b> may pass out of third structure <b>250</b> in any desired location.

0065With further regard to second fluid passage <b>230</b>, the passage can be positioned in any desired location to heat second structure <b>212</b> and may be arranged to allow first thermal transfer fluid <b>240</b> to enter second structure <b>212</b> in any number of locations, e.g., depending on the shape of second structure <b>212</b>. In the nozzle <b>126</b> example shown, second fluid passage <b>230</b> has an inlet <b>242</b> near a circumferential end of mounting rail <b>232</b>.

0066First thermal transfer fluid <b>240</b> may pass through portion(s) of second structure <b>212</b> to heat those portion(s) in a large variety of ways. That is, second fluid passage <b>230</b> can take a large variety of forms to ensure heat transfer to second structure <b>212</b>, e.g., mounting rail <b>232</b>. In <figref idref="DRAWINGS">FIG. <b>5</b></figref>, second fluid passage <b>230</b> has a linear path through mounting rail <b>232</b>. <figref idref="DRAWINGS">FIG. <b>6</b></figref> shows a partially transparent perspective view of turbine component <b>200</b> in which second structure <b>212</b> is also in the form of mounting rail <b>232</b>. In <figref idref="DRAWINGS">FIG. <b>6</b></figref>, second fluid passage <b>230</b> has a non-linear path through second structure <b>212</b>. While shown as a serpentine path, second fluid passage <b>230</b> may have any form of non-linear path, e.g., curved, sinusoidal in a length-wise direction (rather than radially as in <figref idref="DRAWINGS">FIG. <b>5</b></figref>), among many other options. <figref idref="DRAWINGS">FIG. <b>7</b></figref> shows a partially transparent perspective view of turbine component <b>200</b> in which second fluid passage <b>230</b> is sinusoidal in a lengthwise direction within mounting rail <b>232</b>. A cross-sectional shape of second fluid passage <b>230</b> can be any desired shape to foster heat transfer. In certain embodiments, as shown in <figref idref="DRAWINGS">FIG. <b>6</b></figref>, second fluid passage <b>230</b> can be circular in cross-section. In certain embodiments, second fluid passage <b>230</b> may have a non-circular cross-section, e.g., oval or otherwise oblong, polygonal (<figref idref="DRAWINGS">FIGS. <b>5</b>, <b>7</b> and <b>8</b></figref>), or other shapes.

0067Second fluid passage <b>230</b> may also be segmented to include a plurality of fluid passages. For example, <figref idref="DRAWINGS">FIG. <b>8</b></figref> shows three passages <b>230</b>A-C. Any number of passages <b>230</b> can be used. Where a plurality of fluid passages <b>230</b>A-C is used, they may be fluidly coupled by an upstream manifold <b>260</b> at an upstream end <b>262</b> thereof and fluidly coupled by a downstream manifold <b>264</b> at a downstream end <b>266</b> thereof. Upstream manifold <b>260</b> may be fluidly coupled at inlet <b>242</b> to first fluid passage <b>220</b> in first structure <b>210</b>, and downstream manifold <b>264</b> may be fluidly coupled to third fluid passage <b>252</b> in third structure <b>250</b>.

0068Referring to <figref idref="DRAWINGS">FIGS. <b>9</b>-<b>11</b></figref>, in another embodiment, two different heating fluid passages <b>230</b>, <b>280</b> may be provided through second structure <b>212</b>, e.g., mounting rail <b>232</b>. <figref idref="DRAWINGS">FIG. <b>9</b></figref> shows a partially transparent perspective view of turbine component <b>200</b> in the form of nozzle <b>126</b> including two different heating fluid passages <b>230</b>, <b>280</b>; <figref idref="DRAWINGS">FIG. <b>10</b></figref> shows an enlarged, transparent perspective view of a corner (near first structure <b>210</b>) of turbine component <b>200</b>; and <figref idref="DRAWINGS">FIG. <b>11</b></figref> shows an enlarged, transparent perspective view of a corner (near third structure <b>250</b>) of turbine component <b>200</b>. As previously described, second fluid passage(s) <b>230</b> extends through second structure <b>212</b> and is in fluid communication with first fluid passage <b>220</b> in first structure <b>210</b> at one end thereof and with third fluid passage <b>252</b> in third structure <b>250</b> at another end thereof.

0069In the <figref idref="DRAWINGS">FIGS. <b>9</b>-<b>11</b></figref> embodiments, another fluid passage <b>270</b> is defined in third structure <b>250</b> for delivering a second thermal transfer fluid <b>272</b> through at least a portion of third structure <b>250</b>. Second thermal transfer fluid <b>272</b> may include any form of fluid capable of heat transfer, such as air from compressor <b>102</b> (<figref idref="DRAWINGS">FIG. <b>1</b></figref>) or another source. As recognized, second thermal transfer fluid <b>272</b> may enter third structure <b>250</b> in any number of locations. Further, second thermal transfer fluid <b>272</b> may pass through portion(s) of third structure <b>250</b> to cool those portion(s) in a large variety of ways. For example, second thermal transfer fluid <b>272</b> may pass through portions of airfoil <b>176</b> in cooling passages or through impingement sleeves, and/or pass-through portions of platform <b>128</b> or slash faces <b>216</b> in cooling passages defined therein.

0070In the example in <figref idref="DRAWINGS">FIGS. <b>9</b> and <b>11</b></figref> of nozzle <b>126</b>, fluid passage <b>270</b> may be in at least one of airfoil <b>176</b> and platform <b>128</b> for delivering second thermal transfer fluid <b>272</b> therethrough. For purposes of description, fluid passage <b>270</b> is shown mainly within platform <b>128</b>, but it could be in any portion of nozzle <b>126</b> that has a hotter temperature and/or that requires cooling. In any event, a temperature of second thermal transfer fluid <b>272</b> entering third structure <b>250</b> in fluid passage <b>270</b> is less than a temperature of third structure <b>250</b>. Hence, second thermal transfer fluid <b>272</b> in third structure <b>250</b> reduces the temperature of third structure <b>250</b>. While one fluid passage <b>270</b> is illustrated, any number of fluid passages <b>270</b> may be present and feed to fluid passage(s) <b>280</b> in second structure <b>212</b>.

0071In <figref idref="DRAWINGS">FIGS. <b>9</b>-<b>11</b></figref>, another fluid passage <b>280</b> is defined within at least a portion of second structure <b>212</b>. Fluid passage <b>280</b> is in fluid communication with fluid passage <b>270</b> downstream of third structure <b>250</b>. Fluid passage <b>280</b> in second structure <b>212</b> can take any form described herein relative to second fluid passage(s) <b>230</b>, e.g., in terms of number, plenums, linear or non-linear path (e.g., curved or sinusoidal), shape, heat transfer enhancers (<figref idref="DRAWINGS">FIG. <b>12</b></figref>), etc. As noted, a temperature of second thermal transfer fluid <b>272</b> entering third structure <b>250</b> in fluid passage <b>270</b> is less than a temperature of third structure <b>250</b> to reduce the temperature of third structure <b>250</b>. The temperature of second thermal transfer fluid (now labeled <b>282</b>) entering second structure <b>212</b> in fluid passage <b>280</b> is greater than a temperature of second structure <b>212</b> to increase the temperature of second structure <b>212</b>. As shown in <figref idref="DRAWINGS">FIGS. <b>9</b>-<b>11</b></figref>, first thermal transfer fluid <b>240</b> in second fluid passage(s) <b>230</b> in second structure <b>212</b> flows in a first direction in second structure <b>212</b> while second thermal transfer fluid <b>282</b> in fluid passage(s) <b>280</b> in second structure <b>212</b> flows in a second, opposite direction.

0072Once through fluid passage <b>280</b> in second structure <b>212</b>, second thermal transfer fluid (now labeled <b>292</b>) may be used to cool first structure <b>210</b> and/or may be purged through first structure <b>210</b> through another fluid passage <b>290</b> therein. Fluid passage <b>290</b> is in fluid communication with fluid passage <b>280</b> downstream of second structure <b>212</b>. In first structure <b>210</b>, second thermal transfer fluid <b>292</b> includes the same form of fluid as in structures <b>212</b>, <b>250</b>, e.g., air from compressor <b>102</b> (<figref idref="DRAWINGS">FIG. <b>1</b></figref>) or another source, but has a temperature lower than second thermal transfer fluid <b>282</b> when it initially entered second structure <b>212</b>. Second thermal transfer fluid <b>292</b> in first structure <b>210</b> may be used, for example, to cool first structure <b>210</b> and/or as purge gas to prevent ingestion of gases into turbine component <b>200</b> (similarly to the description of thermal transfer fluid <b>254</b> in third structure <b>250</b>). While one fluid passage <b>290</b> is illustrated, any number of fluid passages <b>290</b> may be present to cool first structure <b>210</b> and/or to purge gas from first structure <b>210</b>.

0073Fluid passage(s) provided herein can have any cross-sectional shape described herein, individually or collectively. Where multiple fluid passages are used in any structure <b>210</b>, <b>212</b>, <b>250</b> (e.g., fluid passages <b>230</b>A-C (<figref idref="DRAWINGS">FIGS. <b>7</b>-<b>8</b></figref>) or fluid passage(s) <b>280</b> in second structure <b>212</b>), they can have any cross-sectional shape described herein, individually or collectively. As shown in a schematic perspective view in <figref idref="DRAWINGS">FIG. <b>12</b></figref>, any fluid passage(s) provided herein may also include at least one heat transfer enhancement structure <b>300</b> therein. Heat transfer enhancement structures <b>300</b> can take any form to enhance heat transfer, such as, but not limited to, protrusions, teeth, undulations, etc.

0074As shown in <figref idref="DRAWINGS">FIGS. <b>3</b> and <b>5</b>-<b>8</b></figref>, embodiments of the disclosure also include turbine nozzle <b>126</b>. Nozzle <b>126</b> may include airfoil <b>176</b>, and platform <b>128</b> coupled to airfoil <b>176</b>. Platform <b>128</b> may also include radially extending mounting rail <b>232</b>. First fluid passage <b>220</b> is defined in at least one of airfoil <b>176</b> and platform <b>128</b> for delivering first thermal transfer fluid <b>222</b>, e.g., air, therethrough. Second fluid passage <b>230</b> is defined within at least a portion of a circumferential length (arrow CL in <figref idref="DRAWINGS">FIG. <b>5</b></figref>) of radially extending mounting rail <b>232</b>, and second fluid passage <b>230</b> is in fluid communication with first fluid passage <b>220</b>.

0075Airfoil <b>176</b> and at least one surface <b>214</b> of platform <b>128</b> (e.g., a radially inwardly facing surface <b>214</b> or slash face(s) <b>216</b>) are directly exposed to the HGP of turbine <b>111</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>). Radially extending mounting rail <b>232</b> is not directly exposed to the HGP of turbine <b>111</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>). A temperature of first thermal transfer fluid <b>220</b> entering first fluid passage <b>220</b> in airfoil <b>176</b> or platform <b>128</b> is less than a temperature of airfoil <b>176</b> or platform <b>128</b> to reduce the temperature of airfoil <b>176</b> or platform <b>128</b>. In contrast, the temperature of first thermal transfer fluid <b>240</b> entering second fluid passage <b>230</b> in radially extending mounting rail <b>232</b> is greater than a temperature of radially extending mounting rail <b>232</b> to increase the temperature of mounting rail <b>232</b>. The heating of mounting rail <b>232</b> reduces the temperature difference between it and structure(s) integral to it, e.g., airfoil <b>176</b> and platform <b>128</b>. The reduced temperature difference reduces thermal stress between the parts, e.g., where trailing edge <b>184</b> of airfoil <b>176</b> meets platform <b>128</b> radially inward of mounting rail <b>232</b>. Second fluid passage <b>230</b> may have any number, path, cross-sectional shape, and/or arrangement, as described herein.

0076Nozzle <b>126</b> may also include a downstream structure <b>250</b> (previously referred to as ‘third structure’ or later referred to as ‘additional structure’) integrally coupled to mounting rail <b>232</b> and including third fluid passage <b>252</b> defined within at least a portion thereof. Downstream structure <b>250</b> may include any other part of nozzle <b>126</b>, such as but not limited to at least one of: slash face <b>216</b> of platform <b>128</b>, an exterior surface of airfoil <b>176</b> and trailing edge <b>184</b> (<figref idref="DRAWINGS">FIGS. <b>3</b>, <b>5</b>, <b>7</b> and <b>8</b></figref>, see dashed passage in <figref idref="DRAWINGS">FIG. <b>5</b></figref>) of airfoil <b>176</b>. Third fluid passage <b>252</b> is in fluid communication with second fluid passage <b>230</b> downstream of mounting rail <b>232</b>. First thermal transfer fluid <b>254</b> entering third fluid passage <b>252</b> in downstream structure <b>250</b> may be used for cooling downstream structure <b>250</b> and/or as purge gas to prevent gas ingestion in the noted parts.

0077Nozzle <b>126</b> may also include the structure described relative to <figref idref="DRAWINGS">FIGS. <b>9</b>-<b>11</b></figref>. In these embodiments, fluid passage <b>270</b> is defined in downstream structure <b>250</b> for delivering a second thermal transfer fluid <b>272</b> through at least a portion of downstream structure <b>252</b> (where “downstream” is relative to the flow of thermal transfer fluid <b>272</b> through the fluid passage <b>230</b>). Further, fluid passage <b>280</b> is defined within at least a portion of radially extending mounting rail <b>232</b>. Fluid passage <b>280</b> is in fluid communication with fluid passage <b>270</b> downstream of downstream structure <b>250</b> (that is, fluid passage <b>270</b> being upstream in a flow direction from fluid passage <b>280</b> based on flow through fluid passages <b>270</b>, <b>280</b>). As described, temperature of second thermal transfer fluid <b>272</b> entering downstream structure <b>250</b> in fluid passage <b>270</b> is less than a temperature of downstream structure <b>250</b> to reduce the temperature of downstream structure <b>250</b>. Also, the temperature of second thermal transfer fluid <b>282</b> entering radially extending mounting rail <b>232</b> in fluid passage <b>280</b> is greater than a temperature of radially extending mounting rail <b>232</b> to increase the temperature of mounting rail <b>232</b>. As shown in <figref idref="DRAWINGS">FIG. <b>9</b></figref>, first thermal transfer fluid <b>240</b> in second fluid passage(s) <b>230</b> in mounting rail <b>232</b> flows in a first direction in mounting rail <b>232</b> compared to a second, opposite direction of flow of second thermal transfer fluid <b>282</b> in fluid passage(s) <b>280</b> in mounting rail <b>232</b>.

0078Referring to the flow diagram of <figref idref="DRAWINGS">FIG. <b>13</b></figref>, a method of reducing thermal stress in a turbine component of a turbine, according to embodiments of the disclosure, will now be described. In turbine component <b>200</b> of turbine <b>111</b>, a method may include, in process P<b>1</b>, decreasing a temperature of first structure <b>210</b> of turbine component <b>200</b> by passing (cooler) first thermal transfer fluid <b>222</b> having a temperature lower than first structure <b>210</b> through a first fluid passage <b>220</b> defined in first structure <b>210</b>. The method may also include, in process P<b>2</b>, increasing a temperature of second structure <b>212</b> of turbine component <b>200</b> that is integrally coupled to first structure <b>210</b> by passing (heated) first thermal transfer fluid <b>240</b> through the first fluid passage <b>220</b> in the first structure <b>210</b> through a second fluid passage <b>230</b> defined in the second structure <b>212</b>. At least part of first structure <b>210</b> may be directly exposed to the HGP of turbine <b>111</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>), and second structure <b>212</b> may not be exposed to the HGP of turbine <b>111</b> (<figref idref="DRAWINGS">FIG. <b>2</b></figref>).

0079In process P<b>3</b>, the method may include using first thermal transfer fluid <b>254</b> in third structure <b>250</b> of turbine component <b>200</b> that is integrally coupled to second structure <b>212</b> as a coolant and/or a purge gas. Here, the process may include using first thermal transfer fluid <b>254</b> to cool third (downstream) structure <b>250</b> (passing it through third structure <b>250</b>) and/or using first thermal transfer fluid <b>254</b> as a purge gas by having it exit out of third structure <b>250</b> of turbine component <b>200</b>. Third structure <b>250</b> is integrally coupled to second structure <b>212</b> such that first thermal transfer fluid <b>240</b> passes from second fluid passage <b>230</b> in second structure <b>212</b> through a third fluid passage <b>252</b> defined in third structure <b>250</b> as first thermal transfer fluid <b>254</b> to cool third structure <b>250</b> and/or to exit to an area exterior of third structure <b>250</b>. That is, first thermal transfer fluid <b>254</b> may be used to cool third structure <b>250</b> and/or as a passing (purging) gas out of third structure <b>250</b>. It will be recognized that the flow of <figref idref="DRAWINGS">FIG. <b>13</b></figref> is also applicable to fluid passages <b>270</b>, <b>280</b>, <b>290</b> in the <figref idref="DRAWINGS">FIGS. <b>9</b>-<b>11</b></figref> embodiments. In this case, the order of structures that second thermal transfer fluid <b>272</b>, <b>282</b>, <b>292</b> passes through is reversed, i.e., third structures <b>250</b>, second structure <b>212</b> and then first structure <b>210</b>.

0080Embodiments of the disclosure include heating structure that may be implemented in a turbine component in a turbine to influence and mitigate thermal stresses experienced throughout the component. Heating the structure(s) includes positioning heating fluid passage(s) through selected structures of the turbine component to balance the thermal load in the component and therefore improve component life. The heating arrangement takes used coolant (e.g., spent air) from component cooling circuits and passes it through the target structure to raise its bulk temperature. The methods described herein can be used to increase part life and cycle capability by focusing on cold-side mechanics.

0081The foregoing drawings show some of the processing associated according to several embodiments of this disclosure. In this regard, each process within the flow diagram of the drawings represents a process associated with embodiments of the method described. It should also be noted that in some alternative implementations, the acts noted in the drawings or blocks may occur out of the order noted in the figure or, for example, may in fact be executed substantially concurrently or in the reverse order, depending upon the act involved.

0082Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” “approximately” and “substantially,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be combined and/or interchanged; such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. “Approximately,” as applied to a particular value of a range, applies to both end values and, unless otherwise dependent on the precision of the instrument measuring the value, may indicate +/−10% of the stated value(s).

0083The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present disclosure has been presented for purposes of illustration and description but is not intended to be exhaustive or limited to the disclosure in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the disclosure. The embodiments were chosen and described in order to best explain the principles of the disclosure and the practical application and to enable others of ordinary skill in the art to understand the disclosure for various embodiments with various modifications as are suited to the particular use contemplated.